In this paper a 0.13 μm CMOS front-end for drift chambers is presented. The front-end presents characteristics of low power consumption, which are well-suited in order to implement the cluster counting technique for particles identification. The front-end consists of a Variable Gain Amplifier (VGA) with 0, 10 and 20 dB gain steps and 1 GSa/s 6 bits Analog to Digital Converter (ADC). The VGA power consumption has been optimized according to the selected gain setting. The VGA power consumption is 8.4 mA, 9.4 mA, 10.6 mA for 0, 10, 20 dB gain, respectively.

A 90 nm-CMOS power-optimized analog base- band chain for ultra-low-power impulse-radio ultra-wideband (IR-UWB) receivers is presented. The proposed device merges the functions of a programmable gain amplifier (PGA) and a low-pass filter (LPF). It consists of the cascade of three biquadratic cells made up by opamps in a series-shunt configuration, which features high input impedance, low load effects in the cascade blocks, and better frequency response. The opamp parameters are included in the overall biquad transfer function. This allows getting very low power performance, since the opamp bandwidth is not required to be much larger than the filter cutoff frequency. Moreover, the current consumption is optimized according to the selected gain level (1.3 mA at 0 dB-gain up to 1.9 mA at 40 dB-gain). The PGA features a 0–40 dB programmable gain range with a 5 dB gain-step. The LPF performs a sixth-order 255 MHz low-pass frequency response. For the overall chain the IIP3 is 14 dBm at 0 dB gain, while the input referred noise is 12.5 nV/ Hz at 40 dB gain.

Power consumption of high-speed low-resolution analog-to-digital converters (ADCs) can be reduced by means of calibration. However, this solution has some drawbacks such as time slot allocation for calibration and die area increase. This paper presents a 5-bit 1-Gs/s ADC without calibration, fabricated in 90-nm CMOS. Low power consumption has been ensured by operating at both architecture and comparator levels. A folded interpolated architecture has been adopted. However, compared to standard solutions that use static preamplifiers, the interpolation technique has been implemented by taking recourse to dynamic comparators, enabling significant power saving. Moreover, despite the high operating frequency, intrinsic matching has been ensured while keeping low power consump- tion. The ADC uses double-tail dynamic comparators, operating with a fixed bias current and with reduced kickback noise. Large input transistors are used to guarantee the targeted matching, thereby avoiding calibration. The ADC achieves 4.3b-ENOB (effective number of bits) and 260-MHz effective resolution bandwidth while consuming 7.65 mW from a 1.2 V supply. The ADC figure of meritis 0.39 pJ/conv. step, which is the state-of- the-art performance for an uncalibrated ADC at this sampling frequency and resolution.

In this paper a digital amplitude modulator for a polar transmitter is presented. The instantaneous output power is modulated by adjusting the amplifiers load through a digitally controlled impedance transformation network. The modulator is suited for modulation schemes with moderate peak-to-average DQPSK. The modulator may power ratio (PAPR), such as also be used for fine gain control in constant envelope modulation schemes. A class E amplifier with digital impedance amplitude modulation is integrated in 90 nm CMOS. It achieves a peak output power of 9 dBm with a PAE of 30% when powered from a 1.2 V supply. The measured EVM is 2.6% for a 6 dBm DQPSK modulated signal with 2 Mb/s signal rate at 2.4 GHz RF frequency.

In this paper, a RF-DC voltage multiplier operating at 13.56MHz (in the European HF RFID standard band) with -19dBm sensitivity is presented. It is made by a Dickson's RF-DC rectifier and an additional Pelliconi's charge pump driven by a fully integrated 50kHz ring oscillator. Mathematical model is developed and verified through measurements. Silicon prototypes have been realized in 350nm CMOS technology. Measurements show an output voltage ranging from 0.5V up to 3.11V. © 2015 IEEE.

A low-power analog baseband section suitable for 60-GHz receivers using orthogonal frequency-division multi- plexing (OFDM) with 16 quadrature amplitude modulation (16-QAM) modulation is presented in this paper. Power ef- ficiency is achieved by combining active-RC with source-follower-based topologies in order to synthesize a custom sixth-order transfer function. The complete chain consists of the cascade of a first-order transimpedance amplifier with finely programmable gain, a fourth-order source-follower-based filter, and a coarse gain first-order programmable gain amplifier. The prototype is imple- mented in 90-nm CMOS. It achieves a 1-GHz cutoff frequency and programmable gain from 0 to 20 dB with 1-dB step control, drawing 9.5 mA (0–9 dB gain range) or 10.8 mA (10–20 dB gain range) from a 1-V supply. An 8.2-dBm third-order input intercept point and a 145-dBm/Hz input-referred noise power density are measured at 0- and 20-dB gain, respectively. The entire circuit occupies an area of 390x400um^2.

Simultaneous measurements of air showers with the fluorescence and surface detectors of the Pierre Auger Observatory allow a sensitive search for EeV photon point sources. Several Galactic and extragalactic candidate objects are grouped in classes to reduce the statistical penalty of many trials from that of a blind search and are analyzed for a significant excess above the background expectation. The presented search does not find any evidence for photon emission at candidate sources, and combined p-values for every class are reported. Particle and energy flux upper limits are given for selected candidate sources. These limits significantly constrain predictions of EeV proton emission models from non-transient Galactic and nearby extragalactic sources, as illustrated for the particular case of the Galactic center region.

In this paper, a UHF-RFID power management circuit is presented. It is able to power body sensor networks nodes, starting from -25dBm UHF-RFID input signal power. It is based on an initial Dickson's RF-DC rectifier circuit, followed by an ultra-low-voltage integrated boost converter, realized in 180nm CMOS technology, that is used to further step-up of the rectified DC-voltage and to guarantee the RF-to-load isolation. Measurements demonstrate the ability of the power management circuit to provide 400mV output voltage when a -25dBm continuous wave at 866.5MHz (European UHF RFID frequency) is applied at the input. © 2015 IEEE.

A new analysis of the data set from the Pierre Auger Observatory provides evidence for anisotropy in the arrival directions of ultra-high-energy cosmic rays on an intermediate angular scale, which is indicative of excess arrivals from strong, nearby sources. The data consist of 5514 events above 20 EeV with zenith angles up to 80°recorded before 2017 April 30. Sky models have been created for two distinct populations of extragalactic gamma-ray emitters: active galactic nuclei from the second catalog of hard Fermi-LAT sources (2FHL) and starburst galaxies from a sample that was examined with Fermi-LAT. Flux-limited samples, which include all types of galaxies from the Swift-BAT and 2MASS surveys, have been investigated for comparison. The sky model of cosmic-ray density constructed using each catalog has two free parameters, the fraction of events correlating with astrophysical objects, and an angular scale characterizing the clustering of cosmic rays around extragalactic sources. A maximum-likelihood ratio test is used to evaluate the best values of these parameters and to quantify the strength of each model by contrast with isotropy. It is found that the starburst model fits the data better than the hypothesis of isotropy with a statistical significance of 4.0σ, the highest value of the test statistic being for energies above 39 EeV. The three alternative models are favored against isotropy with 2.7σ–3.2σ significance. The origin of the indicated deviation from isotropy is examined and prospects for more sensitive future studies are discussed.

The azimuthal asymmetry in the risetime of signals in Auger surface detector stations is a source of information on shower development. The azimuthal asymmetry is due to a combination of the longitudinal evolution of the shower and geometrical effects related to the angles of incidence of the particles into the detectors. The magnitude of the effect depends upon the zenith angle and state of development of the shower and thus provides a novel observable, sec(θ)max, sensitive to the mass composition of cosmic rays above 3 × 10^18 eV. By comparing measurements with predictions from shower simulations, we find for both of our adopted models of hadronic physics (QGSJETII-04 and EPOS-LHC) an indication that the mean cosmic-ray mass increases slowly with energy, as has been inferred from other studies. However, the mass estimates are dependent on the shower model and on the range of distance from the shower core selected. Thus the method has uncovered further deficiencies in our understanding of shower modeling that must be resolved before the mass composition can be inferred from sec(θ)max.

We present the bidirectional power line communication system developed in parallel to an electronic board for driving and control of HID (high-intensity discharge) and LED (light-emitting diode) lamps. The communication system, developed to be applied in the sector of public illumination, is been designed to combine high efficiency and reliability with low production costs; it consists indeed of discrete cheap components. The communication system described in this paper implements the technique of transporting digital information over existing power lines, avoiding the issue of installing new cables. Digitized signals can use power line cables through the amplitude voltage and current modulation. The solution proposed is more advantageous compared to communication techniques currently on themarket which are essentially two types, power line carrier (modem for high-voltage lines) or radio (zig-Bee transceiver).

An in-situ calibration of a logarithmic periodic dipole antenna with a frequency coverage of 30MHz to 80MHz is performed. Such antennas are part of a radio station system used for detection of cosmic ray induced air showers at the Engineering Radio Array of the Pierre Auger Observatory, the so-called Auger Engineering Radio Array (AERA). The directional and frequency characteristics of the broadband antenna are investigated using a remotely piloted aircraft carrying a small transmitting antenna. The antenna sensitivity is described by the vector effective length relating the measured voltage with the electric-field components perpendicular to the incoming signal direction. The horizontal and meridional components are determined with an overall uncertainty of 7.4+0.9-0.3% and 10.3+2.8-1.7% respectively. The measurement is used to correct a simulated response of the frequency and directional response of the antenna. In addition, the influence of the ground conductivity and permittivity on the antenna response is simulated. Both have a negligible influence given the ground conditions measured at the detector site. The overall uncertainties of the vector effective length components result in an uncertainty of 8.8+2.1-1.3% in the square root of the energy fluence for incoming signal directions with zenith angles smaller than 60°.

We present a combined fit of a simple astrophysical model of UHECR sources to both the energy spectrum and mass composition data measured by the Pierre Auger Observatory. The fit has been performed for energies above 5 · 1018 eV, i.e. the region of the all-particle spectrum above the so-called “ankle” feature. The astrophysical model we adopted consists of identical sources uniformly distributed in a comoving volume, where nuclei are accelerated through a rigidity-dependent mechanism. The fit results suggest sources characterized by relatively low maximum injection energies, hard spectra and heavy chemical composition. We also show that uncertainties about physical quantities relevant to UHECR propagation and shower development have a non-negligible impact on the fit results.

In this work we present an electronic board for driving and control of High Intensity Discharge (HID) lamps and Light Emitting Diode (LED) lamps. In the last fifteen years we have seen a big expansion of HID lamps for public lighting utilizations. In these last years in the same way the LED technology is developing in public lighting. For these two reasons we will need more and more an electronic device which can drive both HID and LED lamps. The presented electronic board is able to drive six lamps by means of six outputs reconfigurable for HID or LED lamp; in particular five outputs are dedicated to drive only LED lamps, while one output can be set up for HID or LED lamps by user. In this work particular effort was made for energy saving problems. Additionally a communication module is developed for remote control. The presented board is developed with discrete components; in order to minimise the board’s cost and PCB’s area, it is working in progress another board with a fully-integrated ASIC with all the control logic systems, communication module and power factor correction inside.

Atmospheric conditions, such as the pressure (P), temperature (T) or air density (rho proportional to P/T ), affect the development of extended air showers initiated by energetic cosmic rays. We study the impact of the atmospheric variations on the reconstruction of air showers with data from the arrays of surface detectors of the Pierre Auger Observatory, considering separately the one with detector spacings of 1500 m and the one with 750 m spacing. We observe modulations in the event rates that are due to the influence of the air density and pressure variations on the measured signals, from which the energy estimators are obtained. We show how the energy assignment can be corrected to account for such atmospheric effects.

We present a new method for probing the hadronic interaction models at ultrahigh energy and extracting details about mass composition. This is done using the time profiles of the signals recorded with the water- Cherenkov detectors of the Pierre Auger Observatory. The profiles arise from a mix of the muon and electromagnetic components of air showers. Using the risetimes of the recorded signals, we define a new parameter, which we use to compare our observations with predictions from simulations. We find, first, inconsistencies between our data and predictions over a greater energy range and with substantially more events than in previous studies. Second, by calibrating the new parameter with fluorescence measurements from observations made at the Auger Observatory, we can infer the depth of shower maximum Xmax for a sample of over 81,000 events extending from 0.3 to over 100 EeV. Above 30 EeV, the sample is nearly 14 times larger than what is currently available from fluorescence measurements and extending the covered energy range by half a decade. The energy dependence of <Xmax> is compared to simulations and interpreted in terms of the mean of the logarithmic mass. We find good agreement with previous work and extend the measurement of the mean depth of shower maximum to greater energies than before, reducing significantly the statistical uncertainty associated with the inferences about mass composition.

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40 +8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 SM. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.

We report a multi-resolution search for anisotropies in the arrival directions of cosmic rays detected at the Pierre Auger Observatory with local zenith angles up to 80◦ and energies in excess of 4EeV (4 × 1018 eV). This search is conducted by measuring the angular power spectrum and performing a needlet wavelet analysis in two independent energy ranges. Both analyses are complementary since the angular power spectrum achieves a better performance in identifying large-scale patterns while the needlet wavelet analysis, considering the parameters used in this work, presents a higher efficiency in detecting smaller-scale anisotropies, potentially providing directional information on any observed anisotropies. No deviation from isotropy is observed on any angular scale in the energy range between 4 and 8EeV. Above 8EeV, an indication for a dipole moment is captured; while no other deviation from isotropy is observed for moments beyond the dipole one. The corresponding p-values obtained after accounting for searches blindly performed at several angular scales, are 1.3×10−5 in the case of the angular power spectrum, and 2.5×10−3 in the case of the needlet analysis. While these results are consistent with previous reports making use of the same data set, they provide extensions of the previous works through the thorough scans of the angular scales.

AMIGA (Auger Muons and Infill for the Ground Array) is an upgrade of the Pierre Auger Observatory designed to extend its energy range of detection and to directly measure the muon content of the cosmic ray primary particle showers. The array will be formed by an infill of surface water-Cherenkov detectors associated with buried scintillation counters employed for muon counting. Each counter is composed of three scintillation modules, with a 10 m^2 detection area per module. In this paper, a new generation of detectors, replacing the current multi-pixel photomultiplier tube (PMT) with silicon photo sensors (aka. SiPMs), is proposed. The selection of the new device and its front-end electronics is explained. A method to calibrate the counting system that ensures the performance of the detector is detailed. This method has the advantage of being able to be carried out in a remote place such as the one where the detectors are deployed. High efficiency results, i.e. 98% efficiency for the highest tested overvoltage, combined with a low probability of accidental counting (~2 %), show a promising performance for this new system.

Cosmic rays are atomic nuclei arriving from outer space that reach the highest energies observed in nature. Clues to their origin come from studying the distribution of their arrival directions. Using 3 × 10(4) cosmic rays with energies above 8 × 10(18) electron volts, recorded with the Pierre Auger Observatory from a total exposure of 76,800 km(2) sr year, we determined the existence of anisotropy in arrival directions. The anisotropy, detected at more than a 5.2σ level of significance, can be described by a dipole with an amplitude of [Formula: see text] percent toward right ascension αd = 100 ± 10 degrees and declination δd = [Formula: see text] degrees. That direction indicates an extragalactic origin for these ultrahigh-energy particles.

The Advanced LIGO and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gamma-ray burst (GRB) that followed the merger of this binary was also recorded by the Fermi Gamma-ray Burst Monitor (Fermi-GBM), and the Anti-Coincidence Shield for the Spectrometer for the International Gamma-Ray Astrophysics Laboratory (INTEGRAL), indicating particle acceleration by the source. The precise location of the event was determined by optical detections of emission following the merger. We searched for high-energy neutrinos from the merger in the GeV–EeV energy range using the ANTARES, IceCube, and Pierre Auger Observatories. No neutrinos directionally coincident with the source were detected within ±500 s around the merger time. Additionally, no MeV neutrino burst signal was detected coincident with the merger. We further carried out an extended search in the direction of the source for high-energy neutrinos within the 14 day period following the merger, but found no evidence of emission. We used these results to probe dissipation mechanisms in relativistic outflows driven by the binary neutron star merger. The non-detection is consistent with model predictions of short GRBs observed at a large off-axis angle.

A search for ultra-high energy photons with energies above 1EeV is performed using nine years of data collected by the Pierre Auger Observatory in hybrid operation mode. An unprecedented separation power between photon and hadron primaries is achieved by combining measurements of the longitudinal air-shower development with the particle content at ground measured by the fluorescence and surface detectors, respectively. Only three photon candidates at energies 1–2EeV are found, which is compatible with the expected hadron induced background. Upper limits on the integral flux of ultra-high energy photons of 0.027, 0.009, 0.008, 0.008 and 0.007 km−2 sr−1 yr−1 are derived at 95% C.L. for energy thresholds of 1, 2, 3, 5 and 10EeV. These limits bound the fractions of photons in the all-particle integral flux below 0.1%, 0.15%, 0.33%, 0.85% and 2.7%. For the first time the photon fraction at EeV energies is constrained at the sub-percent level. The improved limits are below the flux of diffuse photons predicted by some astrophysical scenarios for cosmogenic photon production. The new results rule-out the early top-down models − in which ultra-high energy cosmic rays are produced by, e.g., the decay of super-massive particles − and challenge the most recent super-heavy dark matter models

We present a search for ultrarelativistic magnetic monopoles with the Pierre Auger observatory. Such particles, possibly a relic of phase transitions in the early Universe, would deposit a large amount of energy along their path through the atmosphere, comparable to that of ultrahigh-energy cosmic rays (UHECRs). The air-shower profile of a magnetic monopole can be effectively distinguished by the fluorescence detector from that of standard UHECRs. No candidate was found in the data collected between 2004 and 2012, with an expected background of less than 0.1 event from UHECRs. The corresponding 90% confidence level (C.L.) upper limits on the flux of ultrarelativistic magnetic monopoles range from 10^−19(cm2 sr s)^−1 for a Lorentz factor γ = 10^9 to 2.5 × 10−21(cm2 sr s)^−1 for γ = 10^12. These results—the first obtained with a UHECR detector—improve previously published limits by up to an order of magnitude.

We present a novel method to measure precisely the relative spectral response of the fluorescence telescopes of the Pierre Auger Observatory. We used a portable light source based on a xenon flasher and a monochromator to measure the relative spectral efficiencies of eight telescopes in steps of 5 nm from 280 nm to 440 nm. Each point in a scan had approximately 2 nm FWHM out of the monochromator. Different sets of telescopes in the observatory have different optical components, and the eight telescopes measured represent two each of the four combinations of components represented in the observatory. We made an end-to-end measurement of the response from different combinations of optical components, and the monochromator setup allowed for more precise and complete measurements than our previous multi-wavelength calibrations. We find an overall uncertainty in the calibration of the spectral response of most of the telescopes of 1.5% for all wavelengths; the six oldest telescopes have larger overall uncertainties of about 2.2%. We also report changes in physics measurables due to the change in calibration, which are generally small.

Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6–16 EeV (E_CM = 110–170 TeV), whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33 +/- 0.16 (1.61 +/- 0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons

This paper presents an integrated, high-sensitivity UHF radio frequency identification (RFID) power management circuit for body sensor network applications. The circuit consists of a two-stage RF-DC Dickson's rectifier followed by an integrated five-stage DC-DC Pelliconi's charge pump driven by an ultralow start-up voltage LC oscillator. The DC-DC charge pump interposed between the RF-DC rectifier and the output load provides the RF to load isolation avoiding losses due to the diodes reverse saturation current. The RF-DC rectifier has been realized on FR4 substrate, while the charge pump and the oscillator have been realized in 180 nm complementary metal oxide semiconductor (CMOS) technology. Outdoor measurements demonstrate the ability of the power management circuit to provide 400 mV output voltage at 14 m distance from the UHF reader, in correspondence of −25 dBm input signal power. As demonstrated in the literature, such output voltage level is suitable to supply body sensor network nodes. ©2016. American Geophysical Union. All Rights Reserved.

On September 14, 2015 the Advanced LIGO detectors observed their first gravitational wave (GW) transient GW150914. This was followed by a second GW event observed on December 26, 2015. Both events were inferred to have arisen from the merger of black holes in binary systems. Such a system may emit neutrinos if there are magnetic fields and disk debris remaining from the formation of the two black holes. With the surface detector array of the Pierre Auger Observatory we can search for neutrinos with energy Eν above 100 PeV from pointlike sources across the sky with equatorial declination from about −65° to +60°, and, in particular, from a fraction of the 90% confidence-level inferred positions in the sky of GW150914 and GW151226. A targeted search for highly inclined extensive air showers, produced either by interactions of downward-going neutrinos of all flavors in the atmosphere or by the decays of tau leptons originating from tau-neutrino interactions in the Earth’s crust (Earth-skimming neutrinos), yielded no candidates in the Auger data collected within +/- 500 s around or 1 day after the coordinated universal time (UTC) of GW150914 and GW151226, as well as in the same search periods relative to the UTC time of the GW candidate event LVT151012. From the non observation we constrain the amount of energy radiated in ultrahigh-energy neutrinos from such remarkable events.

The present invention addresses a need for reducing the power consumption in a baseband filter used in a front-end wireless receiver while providing the necessary linearity. In particular, relatively high linearity can be obtained with lower power consumption than has heretofore been the case. This is achieved in embodiments of the invention using an optimized single-branch fully differential structure which operates as a "composite" source-follower (when using CMOS devices) with an ideal unitary dc gain. A positive feedback internal to the source follower allows one to synthesize two complex-poles.

There is described a continuous time filter of at least a second (or higher) order, comprising one or more first order filter stages of a first type, the or each first order filter stage of the first type comprising a reactive component and an impedance dependent on the difference between the input and output voltages of the filter stage. The filter includes at least one first order filter stage of a second type, the or each second order filter of the second type comprising a reactive component and an impedance dependent on the sum of the input and output voltages of the filter stage. The filter includes a transfer function of the continuous time filter that is obtained comprising complex poles.